Door leaf comprising at least one stone cover plate preferably for an interior door, and method for producing the same

ABSTRACT

The invention relates to a door leaf, preferably for an interior door, and to a method for producing the same. The aim of the invention is to provide a door leaf for a double-wing door or revolving door, which is relatively light-weight and stable and which can be opened using normal force. The outer layer should consist of a layer that is break-proof, scratch-resistant and not susceptible to shocks and should be securely linked with the subject layer without complications. The use of water should be possible during the production of the door without damaging the door leaf. According to the invention, cover plates are glued onto the entire surface of both sides of an inner layer that has a suitable size for a double-wing door or revolving door. At least one of the one-piece cover plates consists of natural stone or artificial stone. During production of the door leaf the inner layer is foamed from high-resistance plastic foam in a mold and is removed from the mold after setting and then glued together with the cover plates. The cover plates are cut down to minimum thicknesses and/or ground down (calibrated). Alternatively, the inner layer is foamed from high-resistance plastic foam in a mold. The cover plates are first inserted in the mold at a distance to each other and then foamed to the inner layer. After setting, the door leaf is removed from the mold and the cover plates are cut down to minimum thicknesses and/or ground down (calibrated).

FIELD OF THE INVENTION

The invention relates to a door leaf, preferably for an interior door, based on the overall concept of Patent claim 1, and a procedure for its manufacture.

BACKGROUND OF THE INVENTION

A folding door is known from DE prototype 84 30 609.2 U1 whose narrow door leaf segments are stiff against deformation, mounted in pivoting links with vertical pivot axes, and are folded individually upon one another in a zigzag pattern into at least one packet in their opened position. Each of the door leaf segments includes a block of closed-pore hard foam, preferably of polyurethane. On both sides of the block, cover plates of solid, monolithic plastic reinforced with mineral or fiberglass fibers are mounted flat or laminated with adhesive.

This solution will publish only segmented door leafs without reference to applicability for double-wing or revolving door leafs.

A house entry door is known from DE 197 01 185 A1 consisting of preferably four layers including an inner layer of wood and an outer layer of natural stone processed before assembly of the door. In this case, an insulation layer and also preferably a carrier layer, particularly of wood, are positioned in order to anchor the outer layer and to combine the layers into a unit, particularly by means of adhesive bonding. In order to anchor the outer layer, the carrier layer is provided with slots to anchor the natural stone plates forming the outer layer. For this, the outer layer is provided with anchoring bushings that engage into the slots of the carrier layer for anchoring by hanging. Also, the outer layer of natural stone is supported elastically with respect to the adjacent carrier layer by means of silicon-rubber points, whereby the anchor bushings of the outer layer also attached elastically using silicone rubber. Connection of the anchor bushings with the outer layer requires a considerable minimum thickness of this outer layer so that the door is heavy, and thus difficult to operate.

Simultaneously, breakage hazard to the stone plates, which possess only low resistance to impact, is increased by the point attachments in the form of anchor bolts.

Further, because of the weight, an outer layer of natural stone with no seams is not practical.

DESCRIPTION OF THE INVENTION

It is the task of the invention to provide a relatively light, strong, double-wing or revolving door leaf that may be opened using normal force whose outer layer consists of a layer that is not susceptible to breakage, impact, or scratching, and that is bound with low cost to the lower layer, whereby the use of water must be possible during door manufacture without damage to the door leaf.

The door leaf Based on the invention is provided by the characteristics of Patent claim 1.

Detailed embodiment examples are described in claims 2 through 4.

The characteristics of the manufacture procedure are specified in Patent claims 5 and 6. Claim 7 describes a potential configuration of both manufacturing procedures.

An advantage of this solution consists of an innovative optical view of a door leaf with a solid covering layer without seams, since the cover layer is of one piece.

The use of hard-foam plastic as an inner layer allows the use of water to process the cover plates made of natural or artificial stone without damage to the door leaf. This allows processing of cover plates to a thickness of 2 or 3 mm. The door leaf weight thus reduced or achieved allows easy operation of the door leaf, particularly upon opening and closing the door.

The invention will now be described in greater using embodiment examples. The proposed door leaf is in the size of a double-wing or revolving door, and should preferably be used for interior doors. The inner layer of the door leaf consists of hard foam, preferably polyurethane. Cover plates are bonded flat on both sides of the inner layer, whereby at least one cover plate consists entirely of natural or artificial stone. Each piece of natural or artificial stone is monolithic. The second cover plate might also be covered using other known materials.

Fiberglass elements or a plastic or melanin epoxy may be positioned between the inner layer and each cover plate to increase strength.

Also, security elements such as plates, armoring, boxed profiles, locks, sensors, and cables and/or edge-protected profiles may be embedded in or attached to the foam. Such items are placed into the mold before foaming the inner layer.

Manufacturing consists of foaming the inner layer in a hard plastic foam mold, removing it from the mold after hardening, and finally bonding it with the cover plates, preferably full-surface. After this, the cover plates are cut and/or ground (calibrated) to minimum thicknesses under a constant supply of water.

Alternatively, the inner layer is foamed within a hard plastic foam mold, whereby the cover plates are pre-positioned in the mold separated from one another and then foam-bonded to the inner layer in that the space between the cover plates are filled with foam. After hardening, the complete door leaf is removed from the mold. Subsequently, the cover plates are cut and/or ground (calibrated) to minimum thicknesses under a constant supply of water.

Upon bonding with the inner layer in final condition, the cover plates have a thickness of about 8 to 20 mm. By cutting and grinding to size, each cover plate is of a thickness of about 2 to 3 mm, so that the door leaf possesses a weight allowing easy operation.

In both manufacturing procedures, the cover plate consisting of natural or artificial stone is additionally provided in advance with a fiberglass mat or a plastic or melanin epoxy plate so that the cover plate may be be bonded to the inner layer by means of it, or is bonded to it by foaming. 

1-7. (canceled)
 8. A procedure to manufacture a door leaf, comprising an inner layer that is first foamed of hard plastic and is bonded with or foamed onto at least one cover plate of natural or synthetic stone and wherein said cover plate is cut ground to a minimum thickness.
 9. The procedure as in claim 8, wherein the hard plastic inner layer is foamed in a mold and removed from the mold after hardening, and wherein the first cover plate of natural or synthetic stone is subsequently bonded to the inner layer and is then cut or ground to a minimum thickness.
 10. The procedure as in claim 8, wherein the inner layer of hard plastic foam is injected directly between two cover plates that were previously placed into a mold separated from each other and bonded to them, and wherein the first cover plate is made of natural or synthetic stone and is cut or ground to a minimum thickness after the inner layer has hardened and been removed from the mold.
 11. The procedure as in claim 8, wherein a fiberglass mat or a plastic or melanin epoxy plate is positioned between at least the first cover plate made of natural or synthetic stone and the inner layer.
 12. The procedure as in claim 11, wherein the fiberglass mat or a plastic or melanin epoxy plate is bonded to the surface of the first cover plate facing the inner layer, and wherein the first cover plate is subsequently bonded with or foamed onto the inner layer via the fiberglass mat or a plastic or melanin epoxy plate.
 13. The procedure as in claim 8, wherein at least one security element selected from the group consisting of plates, armoring, boxed profiles, locks, sensors, and cables or edge-protected profiles, are embedded in or attached to the foam.
 14. The procedure as in claim 8, wherein a second cover plate is also made of natural or synthetic stone that is opposite the first cover plate on the other side of the inner layer, and is processed in the same manner as the first cover plate.
 15. The procedure as in claim 8, wherein the cover plates made of natural or synthetic stone are cut or ground down to a thickness of 2 to 3 mm using water.
 16. The procedure as in claim 8, wherein the cover plates made of natural or synthetic stone have a final thickness of 8 to 20 mm after being bonded with the inner layer.
 17. A door leaf with an inner layer of hard plastic foam and two covering layers shaped as cover plates that are bonded on both sides flat to the inner layer or are foamed onto the inner layer, and wherein at least one cover plate is made of natural or synthetic stone and is monolithic, wherein the cover plates made of natural or synthetic stone have a initial thickness of 8 to 20 mm after being bonded to the inner layer, and are processed down to a final thickness of 2 to 3 mm after bonding.
 18. The door leaf as in claim 17, wherein both cover plates are made of natural or artificial stone, are made in one piece, and are bonded flat to the inner layer or are foamed onto the inner layer.
 19. The door leaf as in claim 17, wherein the inner layer is of polyurethane, and wherein the door leaf is configured for an interior door.
 20. The door leaf as in claim 17, wherein at least one security element selected from the group consisting of plates, armoring, boxed profiles, locks, sensors, and cables or edge-protected profiles, are embedded in or attached to the foam.
 21. The door leaf as in claim 17, wherein a fiberglass mat or a plastic or melanin epoxy plate is positioned between the inner layer and the cover plate. 